Under leadership of Akihiro Uehara a combined electrochemical/X-ray absorption spectroscopy study deconstructing the famous Brust-Schiffrin synthesis of gold nanoparticles has been carried out. The results elucidates some of the transformations taking place during this two-phase synthesis. The results show that the reaction at the oil-water interface includes a time dependent evolution of the Au(I) species formed as intermediates, and identifies the nature of the (also time dependent) thiolate side products.

We recently realised that Near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy at the C K-edge can distinguish between different saccharides because minute variations in average C-O bond lengths manifest as detectable shifts of the shape resonances associated with these bonds. This opens up the possibility for novel analytical approaches, for example to identify different types of sugars in drug formulations or foods:

A windowless electrochemical cell for the spectroscopic investigation of the liquid-liquid interface, using a dual droplet configuration, has been designed. The setup permits in situ probing of the bulk solutions and the interfacial region by fibre-optic UV-vis spectroscopy, microfocus X-ray fluorescence (XRF) elemental mapping, and microfocus X-ray absorption near-edge structure (micro-XANES) spectroscopy. The electrodeposition of Au, induced by ion transfer of the tetrachloroaurate complex from a halogenated solvent (containing a weak reducing agent) to the aqueous phase, has been monitored by a combination of the three techniques. The reaction can be followed in-situ by UV-vis spectroscopy by detecting the oxidised form of the reducing agent. Voltammetric evidence suggests the formation of interfacial Au(I) species, whereas micro-XANES detect the presence of metallic Au(0).

Having made some unexpected impact with our 2009 Surface and Interface Analysis paper on the XPS of saccharides (see here), we are now publishing a conceptually similar paper, this time dealing with the XPS of several amino acids and peptides derived from them: